Construction – Geronimo/370

Another new clock

Posted on2023-07-16

Remember that Making a new clock (1) blog post? That one was to honour my dad’s old nixie clock. It’s in my office / HAM shack. Now we wanted another clock for another room. I decided to use the same parts and the same software, but built it a lot… Read the rest

Making a new clock (1)

Posted on2023-01-022023-01-202 Comments

As you could have read in my previous post, I decided to create my own digital clock to replace the old nixie clock (R.I.P). Components The components I will be using are: The casing of the old nixie clock An Arduino Uno (for programming the ATMEGA328p chip. Actually that chip… Read the rest

Fixing old Nixie Clock (3) ?

Posted on2023-01-021 Comment

Well, maybe you remember the previous posts about my dad’s nixie clock? I was very satisfied when I got it working again. Now, after 8 months it finally broke down completely. Oh well, it lasted for (I think) over forty years! New beginnings I decided to take the guts out… Read the rest

Common mode filters

Posted on2022-05-212022-05-214 Comments

This afternoon, I will be taking my Novice exam. So in preparation of being allowed to transmit, I decided to create a barrier for HF. I did so by making a number of loops (7) in the coax cables, just above the ceiling. These loops act as coils and they… Read the rest

Fixing old Nixie Clock (3)

Posted on2022-04-282022-04-28

Capacitor replaced The replacement of the power supply capacitor with a new one cleaned up the pulses nicely. The clock is running properly again for about two days now.… Read the rest

Fixing old Nixie Clock (1)

Posted on2022-04-102022-11-22

Father’s clock My father built a Nixie clock in ‘ye olden days‘, over forty years ago… It was a relatively simple design compared to what we build nowadays. Design and simplified workings The clock derives it’s clock-pulses from the mains power, 50 Hz here in the Netherlands Dividing it by… Read the rest

Retro Z80 computer (9) – BLINKENLIGHTS

Posted on2022-01-212022-01-21

A small project today. I added ‘BLINKENLIGHTS’ to my Z80. This term stems from an old sign that used to hang in computer rooms: ACHTUNG!ALLES TURISTEN UND NONTEKNISCHEN LOOKENSPEEPERS!DAS KOMPUTERMASCHINE IST NICHT FÜR DER GEFINGERPOKEN UND MITTENGRABEN! ODERWISE IST EASY TO SCHNAPPEN DER SPRINGENWERK, BLOWENFUSEN UND POPPENCORKEN MIT SPITZENSPARKEN.IST NICHT… Read the rest

Retro Z80 computer (7) – Almost complete

Posted on2021-12-212021-12-22

Here’s a picture of the progress so far. It now also includes a RTC (Real Time Clock) module. What you might also notice is the flat cable I attached between the serial card and the serial to USB connector. That connector, as you can see in previous posts, was attached… Read the rest

Retro Z80 computer (6) – It works!

Posted on2021-12-16

I am one happy maker, I got my Z80 computer working right after building. All went well! The first lines of output are the boot screen: CP/M And of course I wanted to see CP/M running: Z80 Basic And after that, on to Z80 Basic version4.7b:… Read the rest

Retro Z80 computer (5) – Dual Clock Module

Posted on2021-12-162021-12-16

Without an internal clock nothing happens inside a computer. It’s the clock that makes the computer ‘tick’, chew away instructions that is. Last I assembled this module; it contains two clocks. Both clock signals are being put on the bus on the Backplane board. It’s starting to look like something…… Read the rest

Retro Z80 computer (4) – Dual Serial Module

Posted on2021-12-15

And another one bites the dust… The Dual Serial SIO/2 module has been assembled and soldered. With this one I had to search for the value of the resistors, because the info was not in the documentation. Eventually I ended up looking at the pictures of an assembled one online… Read the rest

Retro Z80 computer (3) – Memory module

Posted on2021-12-152021-12-15

And the memory module for my Z80 computer is finished. It contains 512K of ROM and 512K of RAM memory.… Read the rest

Retro Z80 computer (2) – backplane and CPU board

Posted on2021-12-152021-12-15

Yesterday evening I assembled and soldered the backplane board and the CPU board. Around 600 solder joints…… Read the rest

Retro Z80 computer (1) – plans

Posted on2021-12-112021-12-15

This holiday season I’m going retro, and build my own Z80 computer from a kit. The kit offers all the separate parts and one has to assemble the whole thing… All the parts Modular design The design of this computer is totally modular. Because it has been thought out very… Read the rest

HAM-gadget (6) – adjustment & enclosure

Posted on2021-11-132021-11-13

In this version I built in the possibility to adjust the summer and wintertime offset from UTC. It’s a very crude offset, I just add or subtract the offset from the UTC hour. Have to think of a better way to do this… Enclosure I built in the gadget in… Read the rest